Parallel RC circuit equalizers

ABSTRACT

Disclosed are apparatus and methodology for increasing the resonance frequency and useful frequency range of surface mount RC equalizer devices. The presently disclosed subject matter provides improved operational characteristics of generally known such RC equalizer devices by implementing a reverse geometry that relocates the internal termination points, as well as external termination points for such devices, along lateral portions of the assembled device. Such reverse geometry achieves improvements by providing a reduction of the equivalent series inductance (ESL) to provide the increased resonance frequency and useful frequency range.

PRIORITY CLAIM

This application claims the benefit of previously filed U.S. ProvisionalPatent Application entitled “PARALLEL RC CIRCUIT EQUALIZERS,” assignedU.S. Ser. No. 62/149,968, filed Apr. 20, 2015, and which is incorporatedherein by reference for all purposes.

FIELD OF THE SUBJECT MATTER

The presently disclosed subject matter relates to surface mountableglass sandwich flex-terminated RC circuits. In particular, the presentlydisclosed subject matter relates to improvements in such surface mountdevices that provides for reduction of the equivalent series inductance(ESL) to provide increased resonance frequency and useful frequencyrange. When used in an optical device, that allows the equalizer tobetter attenuate lower frequencies and accentuate higher frequencies inorder to compensate for frequency dependence.

BACKGROUND OF THE SUBJECT MATTER

Circuit equalizers may be used in various forms including ascompensation for signal losses and/or degradation over conductors onprinted circuit assemblies among other applications. Such devicesoperate by passively adjusting the impedance characteristic of thesignal pathway and have applicability in a broad range of applicationsincluding optical transceiver modules, broadband receivers, TransmitOptical Sub-Assemblies (TOSA), Receive Optical Sub-Assemblies (ROSA),and various other high frequency devices.

Known surface mountable RC equalizer circuits have addressed issuesincluding resonant frequency and useful frequency range but have notprovided a device that meets current desirable operational requirements.It would be advantageous, therefore, if a device could be provided thatprovided both increased resonance frequency and useful frequency range.

SUMMARY OF THE SUBJECT MATTER

In view of the recognized features encountered in the prior art andaddressed by the presently disclosed subject matter, improvedapparatuses and methodologies have been developed that provide forreducing equivalent series inductance (ESL) in a surface mountable RCequalizer circuit to thereby permit increasing resonance frequency witha larger useful frequency range.

In accordance with one aspect of an exemplary embodiment of thepresently disclosed subject matter, a parallel connected RC circuit hasbeen provided wherein termination points are configured to providereduced ESL for the RC devices. In some embodiments of the presentlydisclosed subject matter, such reduced ESL is provided by selectiveplacement of termination material along an extended portion of theassembled device.

In accordance with another aspect of an exemplary embodiment of thepresently disclosed subject matter, a parallel RC equalizer circuit maybe configured based on the structure of a coplanar waveguide. In somesuch embodiments, reduced ESL may be provided by inclusion of acentrally located and extended ground termination. In such embodiments,the ground termination may correspond to a termination centrally locatedbetween longitudinal placed ports on the device.

In accordance with additional aspects of some embodiments of thepresently disclosed subject matter, methodologies have been developedfor reducing ESL in a parallel RC circuit device wherein selectiveplacement of termination material and internal connections to suchtermination material produce the desired reduction in ESL andconsequently provide for improvements in both resonance frequency anduseful frequency range.

One exemplary embodiment of the presently disclosed subject matterrelates to a parallel RC circuit equalizer having relatively increasedresonance frequency and useful frequency range. Such exemplary equalizerpreferably comprises a monolithic substrate, a capacitor, first andsecond terminal layers, a resistor, and at least one connection terminalassociated with such resistor. Such exemplary arrangement of suchterminal layers and such at least one connection terminal results inreduced equivalent series inductance of such capacitor, which relativelyincreases the resonance frequency and useful frequency range of theresistor and capacitor combined circuit.

In the foregoing exemplary embodiment, preferably such monolithicsubstrate has at least a top surface and at least one pair of opposinglateral edges along such top surface of such substrate; such capacitorhas a first electrode layer and a second electrode layer, with bothelectrode layers mounted on such top surface of such substrate, andseparated by a dielectric; such first terminal layer is connected tosuch first electrode layer and positioned on such top surface of suchsubstrate and along at least a portion of one of such lateral edgesthereof; such second terminal layer is connected to such secondelectrode layer and positioned on such top surface of such substrate andalong at least a portion of such lateral edge thereof opposite to suchfirst terminal layer; and such resistor is supported on such substratetop surface and connected in parallel with such capacitor.

In variations of the foregoing, a cover may be included above suchsubstrate; and a pair of terminations may be provided on either lateralside of such substrate, and respectively connected with such first andsecond terminal layers, whereby such equalizer is surface mountable bydirect mounting of such terminations on a supporting surface. In furthervariations, such cover may comprise a glass cover, and such terminationsmay comprise flexible terminations.

In still other variations, such flexible terminations may compriseflexible polymer material that encases end portions of such capacitor.In some variations thereof, one of such flexible terminations may couplesuch first terminal layer connected to such first electrode layer ofsuch capacitor with such at least one connection terminal associatedwith such resistor. In others, one of such flexible terminations maycouple with such second terminal layer connected to such secondelectrode layer of such capacitor.

In yet other alternative arrangements of the foregoing exemplaryequalizer embodiment, such capacitor may comprise a silicon oxynitride(SiON) capacitor or a tantalum capacitor; and such resistor may comprisea tantalum nitride (TaN) resistor or a ruthenium oxide resistor. In someexemplary embodiments of the foregoing, such equalizer may have animpedance of about 50Ω between such pair of terminations on eitherlateral side of such substrate.

In other variations, such an exemplary equalizer may further include aglass cover above such substrate; and a pair of flexible terminations oneither lateral side of such substrate, and respectively connected withsuch first and second terminal layers so that such equalizer is surfacemountable; with such flexible terminations comprising flexible polymermaterial that encases end portions of such capacitor; with one of suchflexible terminations coupling such first terminal layer connected tosuch first electrode layer of such capacitor with such at least oneconnection terminal associated with such resistor; and the other of suchflexible terminations coupling with such second terminal layer connectedto such second electrode layer of such capacitor.

In yet another presently disclosed exemplary embodiment, a parallel RCcircuit equalizer preferably has relatively increased resonancefrequency and useful frequency range. Such equalizer preferablycomprises a monolithic substrate having at least a top surface and atleast one pair of opposing lateral edges along such top surface of suchsubstrate, such substrate being elongated along such opposing lateraledges thereof and having respective opposite end edges; a capacitormounted on such top surface of such substrate; a resistor supported onsuch substrate top surface and connected in parallel with suchcapacitor; a pair of respective waveguide elements connected with theground, and supported on such top surface of such substrate so as toextend respectively to such respective opposite end edges of suchsubstrate; and a pair of ground electrodes positioned on such topsurface of such substrate and respectively extending along at least aportion of such opposing lateral edges of such top surface of suchsubstrate. Such arrangement of such elements and such electrodespreferably results in reduced equivalent series inductance of suchcapacitor, which relatively increases the resonance frequency and usefulfrequency range of the resistor and capacitor combined circuit.

In alternatives of the foregoing exemplary embodiment, such equalizermay further include a cover above such substrate; and a pair of endterminations on either end of such substrate. Such end terminations arepreferably respectively connected with such pair of respective waveguideelements, whereby such equalizer is surface mountable by direct mountingof such terminations on a supporting surface. Other variations mayfurther include a ground termination centrally received about at least aportion of such substrate and connecting with such pair of groundelectrodes.

Still further, in some instances such cover may comprise a glass cover;and such pair of end terminations and such ground termination maycomprise flexible terminations. In other instances, such flexibleterminations may comprise flexible polymer material. In some of theforegoing variations, such capacitor may comprise a silicon oxynitride(SiON) capacitor or a tantalum capacitor; and such resistor may comprisea tantalum nitride (TaN) resistor or a ruthenium oxide resistor.

In some exemplary embodiments of the foregoing, such equalizer may havean impedance of about 50Ω between such pair of end terminations.

It is to be understood from the complete disclosure herewith that thepresently disclosed subject matter equally pertains to correspondingand/or associated methodology. One exemplary embodiment of methodologyfor relatively increasing the resonance frequency and useful frequencyrange of a parallel RC circuit equalizer, may preferably compriseproviding a monolithic substrate having at least a top surface and atleast one pair of opposing lateral edges along such top surface of suchsubstrate, such substrate being elongated along such opposing lateraledges thereof and having respective opposite end edges; supporting acapacitor on such top surface of such substrate; supporting a resistoron such substrate top surface and connected in parallel with suchcapacitor so as to form an RC circuit therewith; and providingtermination material positioned on such top surface of such substrateand along at least a portion of each of such opposing lateral edgesthereof, resulting in reduced equivalent series inductance of suchcapacitor, which relatively increases the resonance frequency and usefulfrequency range of the resistor and capacitor combined circuit.

Some variations of the foregoing methodology may further includeproviding at least a pair of coplanar waveguide elements supported onsuch substrate and aligned lengthwise along a center line of suchsubstrate, with such waveguide elements received in series and on eitherside of such RC circuit and extending from such RC circuit to therespective opposite end edges of such substrate. In come suchvariations, such providing termination material may include providing apair of ground electrodes positioned respectively along such lateraledges of such substrate. Yet others may further include providing acover above such substrate; and providing a pair of flexibleterminations received at respective opposite end edges of suchsubstrate, and respectively connected with such waveguide elements atsuch opposite end edges.

Still further variations may also include providing a ground terminalreceived at least partly around such substrate and connected with suchpair of ground electrodes. In some such alternatives, such flexibleterminations may comprise flexible polymer material; such capacitor maycomprise one of a silicon oxynitride (SiON) capacitor and a tantalumcapacitor; and such resistor may comprise one of a tantalum nitride(TaN) resistor and a ruthenium oxide resistor.

For some alternatives, presently disclosed methodology may furtherinclude surface mounting such equalizer on a supporting surface.

In other presently disclosed variations, such capacitor may have a firstelectrode layer and a second electrode layer, with both of suchelectrode layers mounted on such top surface of such substrate, andseparated by a dielectric; and such termination material may include afirst terminal layer connected to such first electrode layer andpositioned on such top surface of such substrate and along at least aportion of one of such lateral edges thereof, and a second terminallayer connected to such second electrode layer and positioned on suchtop surface of such substrate and along at least a portion of suchlateral edge thereof opposite to such first terminal layer.

Still other variations may further include providing at least oneconnection terminal associated with such resistor; and providing a coverabove such substrate, and a pair of terminations on either lateral sideof such substrate, and respectively connected with such first and secondterminal layers.

Also, other variations may further include a glass cover above suchsubstrate; and a pair of flexible terminations on either lateral side ofsuch substrate, and respectively connected with such first and secondterminal layers so that such equalizer is surface mountable; and withsuch flexible terminations comprising flexible polymer material thatencases end portions of such capacitor; with one of such flexibleterminations coupling such first terminal layer connected to such firstelectrode layer of such capacitor with such at least one connectionterminal associated with such resistor; and with the other of suchflexible terminations coupling with such second terminal layer connectedto such second electrode layer of such capacitor.

Additional embodiments of the presently disclosed subject matter are setforth in, or will be apparent to, those of ordinary skill in the artfrom the detailed description herein. Also, it should be furtherappreciated that modifications and variations to the specificallyillustrated, referred and discussed features and elements hereof may bepracticed in various embodiments and uses of the subject matter withoutdeparting from the spirit and scope of the subject matter. Variationsmay include, but are not limited to, substitution of equivalent means,features, or steps for those illustrated, referenced, or discussed, andthe functional, operational, or positional reversal of various parts,features, steps, or the like.

Still further, it is to be understood that different embodiments, aswell as different presently preferred embodiments, of the presentlydisclosed subject matter may include various combinations orconfigurations of presently disclosed features, steps, or elements, ortheir equivalents (including combinations of features, parts, or stepsor configurations thereof not expressly shown in the figures or statedin the detailed description of such figures). Additional embodiments ofthe presently disclosed subject matter, not necessarily expressed in thesummarized section, may include and incorporate various combinations ofaspects of features, components, or steps referenced in the summarizedobjects above, and/or other features, components, or steps as otherwisediscussed in this application. Those of ordinary skill in the art willbetter appreciate the features and aspects of such embodiments, andothers, upon review of the remainder of the specification.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the presently disclosed subjectmatter, including the best mode thereof, directed to one of ordinaryskill in the art, is set forth in the specification, which makesreference to the appended figures, in which:

FIG. 1 illustrates the internal configuration of a previously knownresistor and parallel connected capacitor (RC) construction;

FIG. 2 illustrates the parallel RC device of FIG. 1 with glass cover andflexible terminations;

FIG. 3 illustrates graphic response curves related to the previouslyknown device illustrated in FIGS. 1 and 2;

FIG. 4 illustrates an equivalent circuit diagram for the previouslyknown device illustrated in FIGS. 1 and 2;

FIG. 5 illustrates an exemplary embodiment of internal configuration ofa resistor and parallel connected capacitor in accordance with thepresently disclosed subject matter;

FIG. 6 illustrates an exemplary parallel RC device constructed inaccordance with FIG. 5 with glass cover and flexible terminations inaccordance with the presently disclosed subject matter;

FIG. 7 illustrates graphic response curves related to the deviceillustrated in FIGS. 5 and 6;

FIG. 8 illustrates an equivalent circuit diagram for the exemplarydevice illustrated in FIGS. 5 and 6;

FIG. 9 illustrates an exemplary embodiment of a parallel RC deviceconstructed in accordance with an alternative embodiment of thepresently disclosed subject matter;

FIG. 10 illustrates an exemplary parallel RC device constructed inaccordance with FIG. 9 with glass cover and flexible terminations inaccordance with the presently disclosed subject matter;

FIG. 11 illustrates graphic response curves related to the exemplarydevice illustrated in FIGS. 9 and 10; and

FIG. 12 illustrates an equivalent circuit diagram for the exemplarydevice illustrated in FIGS. 9 and 10.

Repeat use of reference characters throughout the present specificationand appended drawings is intended to represent same or analogousfeatures or elements.

DETAILED DESCRIPTION OF THE SUBJECT MATTER

As discussed in the Summary of the Subject Matter section, the presentlydisclosed subject matter is particularly concerned with improvements tosurface mount parallel connected RC devices that provides for reductionof the equivalent series inductance (ESL) to provide increased resonancefrequency and useful frequency range.

Selected combinations of aspects of the disclosed technology correspondto a plurality of different embodiments of the presently disclosedsubject matter. It should be noted that each of the exemplaryembodiments presented and discussed herein should not insinuatelimitations of the presently disclosed subject matter. Features or stepsillustrated or described as part of one embodiment may be used incombination with aspects of another embodiment to yield yet furtherembodiments. Additionally, certain features may be interchanged withsimilar devices or features not expressly mentioned which perform thesame or similar function.

Reference is made hereafter in detail to exemplary presently preferredembodiments of the subject parallel RC circuit equalizer. Referring tothe drawings, FIGS. 1-4 illustrate a previously known parallel RCcircuit equalizer 100, 200 (FIGS. 1-2) together with operationalcharacteristic curves 300 (FIG. 3) and related equivalent circuit 400therefor (FIG. 4). As may be seen in FIG. 1, RC circuit equalizer 100corresponds to a glass substrate 102 on which are mounted a capacitor104 and resistor 106.

In accordance with such known device, capacitor 104 may correspond to asilicon oxynitride (SiON) capacitor having a first electrode 108 thereofcoupled to a conductive trace 110 on substrate 102 via conductor 112. Aswill be understood by those of ordinary skill in the art, capacitor 106also includes a second electrode (not seen) below first electrode 108and separated therefrom via a SiON layer (also not seen). Such secondelectrode (unseen in this view) is coupled to one end of resistor 106and to connection terminal 114. Resistor 106 is further coupled at asecond end thereof to connection terminal 116.

With reference to FIG. 2, there is illustrated the parallel RC device200 of FIG. 1 with glass cover and flexible terminations 202, 204 added.Flexible terminations 202, 204 may correspond to a flexible polymermaterial that encases the end portions 208, 210 of capacitor 200 andcouples terminals 110, 116 together and provides an external connectionpoint for connection terminal 114.

With reference to FIG. 3, there are illustrated graphic response curves300 related to the device illustrated in FIGS. 1 and 2. Those ofordinary skill in the art will appreciate that the notations S₁₁ and S₂₁represent reflection and forward transmission coefficients,respectively, for the RC circuit. From an inspection of FIG. 3, it willbe noticed that the forward transmission coefficient for a simulatedmodel, S₂₁M, and for that of the equivalent circuit illustrated in FIG.4, S₂₁E, track with minimum variations. Similarly, the reflectioncoefficients for a simulated model, S₁₁M, and that of the equivalentcircuit, S₁₁E, also track with only minor variations.

As understood by those of ordinary skill in the art, the values of S₁₁and S₂₁ are plotted, as illustrated in FIG. 3, in terms of frequencyversus attenuation or gain. An inspection of FIG. 3 shows that theresonance frequency for the device illustrated in FIGS. 1 and 2 is quitelow on the frequency scale while the usable frequency range begins todrop off rapidly above resonance. As an example, the frequency scale ofthis example corresponds to 100-300,000 MHZ so that the resonance pointis below about 3,000 MHz.

With reference to FIG. 4, there is illustrated an equivalent circuitdiagram for the device illustrated in FIGS. 1 and 2. As noted above andillustrated in FIG. 3, the response curves for the equivalent circuitwell track a simulation of the circuit. In one example, the values forinductors 402 and 404 were equivalent and corresponded to 0.287 nH.Similarly the values for capacitors 408 and 410 were equal andcorresponded to 0.062 pF. Inductor 406 had a value of 0.071 nH whilecapacitor 412 had a value of 17.684 pF and resistor 414 had a value22.084Ω. Such values produced a characteristic impedance (Z₀) of 50Ω atboth the input port 416 and output port 418.

With reference to FIG. 5, the internal configuration of a resistor 506and parallel connected capacitor 504 of an RC circuit equalizer 500 inaccordance with the presently disclosed subject matter is illustrated.From a comparison with the device illustrated in FIG. 1 and that of FIG.5 constructed in accordance with the presently disclosed subject matter,it will be noticed that the internal components have some similaritiesbut with the exception of the arrangement of the connection terminals520, 514, 512, 518. In accordance with the presently disclosed subjectmatter, RC equalizer 500 is arranged in a transverse geometry from thatillustrated in FIG. 1. As is further described herein, suchrearrangement provides reduced ESL of capacitor 504, thereby increasingthe resonance frequency of the RC parallel circuit as well as thecircuit's useful frequency range.

In some exemplary embodiments of the presently disclosed subject matter,capacitor 504 may be provided as a silicon oxynitride (SiON) capacitorwhile resistor 506 may correspond to a tantalum nitride (TaN) resistor.Those of ordinary skill in the art should appreciate, however, that bothcapacitor 504 and resistor 506 may be provided using any suitablematerials and configurations. For example, tantalum capacitors and/orruthenium oxide resistors might be used.

With continued reference to FIG. 5, it will be noticed that capacitor504 in some ways is constructed in similar manner to capacitor 104 ofFIG. 1 in that there is provided a first electrode layer 508 separatedby a dielectric (not seen in this view) from a second electrode layer510 both mounted on the top surface of a glass substrate 502. Firstelectrode layer 508 is provided with a terminal layer 520 that ispositioned on the top surface and along a portion of the lateral edge ofsubstrate 502. Similarly, a second electrode 510 is provided with aterminal layer 514 in contact with second electrode layer 510 andpositioned along the lateral edge of the top surface of substrate 502opposite to terminal layer 520.

With reference to FIG. 6, there is illustrated a parallel RC device 600(device 500 of FIG. 5) with glass cover 602 and flexible terminations604, 606 added. Flexible terminations 604, 606 may correspond to aflexible polymer material that encases the end portions 608, 610 of thecapacitor and couples terminals 518, 520 (FIG. 5) together and providesan external connection point for connection terminal 614, respectively.It should be appreciated that while the use of flexible terminationmaterial has been illustrated, other known termination materials may beused as well.

With reference to FIG. 7, there are illustrated graphic response curves700 related to the exemplary device illustrated in FIGS. 5 and 6. Froman inspection of FIG. 7, it will be noticed that the forwardtransmission coefficient S₂₁M for a simulated model and for that of theequivalent circuit S₂₁E illustrated in FIG. 8, track exactly and arethus illustrated as a single line S₂₁EM. Similarly, the reflectioncoefficients S₁₁M for a simulated model and that of the equivalentcircuit S₁₁E also track exactly and are illustrated as single lineS₁₁EM.

An inspection of FIG. 7 shows that the resonance frequency for thedevice illustrated in FIGS. 5 and 6 is higher on the frequency scalethan that illustrated in the curves 300 of FIG. 3 while the usablefrequency range starts to drop off at a much higher frequency. As withthe curves illustrated in FIG. 3, the frequency scale of this examplecorresponds to 100-300,000 MHZ so that the resonance point is aboveabout 3,000 MHz.

With reference to FIG. 8, there is illustrated an equivalent circuitdiagram for the exemplary device illustrated in FIGS. 5 and 6. As notedabove and as illustrated in FIG. 7, the response curves for theequivalent circuit track the simulation of the circuit exactly. In oneexample, the values for inductors 802 and 804 were equivalent andcorresponded to 0.091 nH. Similarly the values for capacitors 808 and810 were equal and corresponded to 0.028 pF. Inductor 806 had a value of0.075 nH while capacitor 812 had a value of 18.019 pF and resistor 814had a value 22.769Ω. In such equivalent circuit, inductor 806 had avalue of 0.075 nH while inductor 820 had a value of 0.11 nH. Resistor822 had a value of 0.07Ω. As was obtained also in the equivalent circuitof FIG. 4, the equivalent circuit if FIG. 7 produced a characteristicimpedance (Z₀) of 50Ω at both the input port 816 and output port 818.

With reference to FIG. 9, there is illustrated a parallel RC device 900constructed in accordance with an alternative embodiment of thepresently disclosed subject matter. More specifically, RC device 900 isconstructed with an internal structure based on a coplanar waveguide. Asillustrated in FIG. 9, the coplanar waveguide structure includeswaveguide elements 902, 904 aligned lengthwise along a center line 908of the upper surface 910 of an elongated glass substrate 912. Aresistor-capacitor (RC) structure 914 is provided between the twowaveguide elements 902, 904. RC structure 914 is configured to provide aparallel RC circuit coupled in series with the two waveguides 902, 904.

A pair of ground electrodes 920, 922 is positioned along lateral edges916, 918 of glass substrate 912. Side edges of ground electrodes 920,922 each extend to the lateral edges of their respective lateral edges916, 918 of glass substrate 912 to provide connection points for aground terminal otherwise described herein.

With reference to FIG. 10, there is illustrated a parallel RC device1000 constructed in accordance with the device illustrated in FIG. 9with glass cover 1002 and flexible terminations 1004, 1006, 1008 addedin accordance with the presently disclosed subject matter. In anexemplary configuration, glass cover 1002 may be secured to glasssubstrate 1012 via an epoxy layer (not separately illustrated). In oneexemplary embodiment, such epoxy layer may be approximately 10 μm thick.Ground electrodes 1020, 1022 are each arranged such that the lateraledges thereof proximate the lateral edges of glass substrate 1012 arecontacted by flexible termination 1008 which functions as a groundterminal for coplanar waveguide RC device 1000.

Further, waveguide elements 902, 904 (FIG. 9) are arranged such that thelongitudinal ends thereof proximate the longitudinal ends of glasssubstrate 1012 are arranged such that they may be contacted by flexibleterminations 1004, 1006, respectively. In such manner, flexibleterminations 1004, 1006 function as input and output ports,respectively, for RC device 1000.

FIG. 11 illustrates graphic response curves 1100 related to theexemplary alternative embodiment device illustrated in FIGS. 9 and 10.From an inspection of FIG. 11, it will be noted that the S₂₁ curves ofthe modeled device S₂₁M and that of the equivalent circuit S₂₁Eillustrated in FIG. 12 track each other almost exactly. Further, itshould be appreciated that in such embodiment of the presently disclosedsubject matter, the usable frequency range extends somewhat higher thanthat of the embodiment illustrated in FIGS. 5-8 and significantly higherthan that of the previously known device illustrated in FIGS. 1-4.

With reference to FIG. 12, there is illustrated an equivalent circuitdiagram for the exemplary alternative embodiment device illustrated inFIGS. 9 and 10. As noted above and illustrated in FIG. 11, the responsecurves for the equivalent circuit track each other almost exactly. Inone example, the value for transmission line inductor 1202 was 5.371 nH.In such example, transmission line inductor 1204 had a value of 4.918nH. Similarly, the values for capacitors 1208 and 1210 were equal andcorresponded to 0.064 pF. Resistor 1222 had a value of 0.0841Ω andresistor 1214 had a value of 35.719Ω. As was obtained also in theequivalent circuit of FIG. 8, the equivalent circuit of FIG. 12 produceda characteristic impedance (Z₀) of 50Ω at both the input port 1216 andoutput port 1218.

While the presently disclosed subject matter has been described indetail with respect to specific embodiments thereof, it will beappreciated that those skilled in the art, upon attaining anunderstanding of the foregoing may readily produce alterations to,variations of, and equivalents to such embodiments. Accordingly, thescope of the present disclosure is by way of example rather than by wayof limitation, and the subject disclosure does not preclude inclusion ofsuch modifications, variations and/or additions to the presentlydisclosed subject matter as would be readily apparent to one of ordinaryskill in the art.

What is claimed is:
 1. A parallel RC circuit equalizer having relativelyincreased resonance frequency and useful frequency range, comprising: amonolithic substrate having at least a top surface and at least one pairof opposing lateral edges along said top surface of said substrate; acapacitor having a first electrode layer and a second electrode layer,both electrode layers mounted on said top surface of said substrate, andseparated by a dielectric; a first terminal layer connected to saidfirst electrode layer and positioned on said top surface of saidsubstrate and along at least a portion of one of said lateral edgesthereof; a second terminal layer connected to said second electrodelayer and positioned on said top surface of said substrate and along atleast a portion of said lateral edge thereof opposite to said firstterminal layer; a resistor supported on said substrate top surface andconnected in parallel with said capacitor; and at least one connectionterminal associated with said resistor; wherein such arrangement of saidterminal layers and said at least one connection terminal results inreduced equivalent series inductance of said capacitor, which relativelyincreases the resonance frequency and useful frequency range of theresistor and capacitor combined circuit.
 2. A parallel RC circuitequalizer as in claim 1, wherein: said capacitor comprises a siliconoxynitride (SiON) capacitor; and said resistor comprises a tantalumnitride (TaN) resistor.
 3. A parallel RC circuit equalizer as in claim1, wherein: said capacitor comprises a tantalum capacitor; and saidresistor comprises a ruthenium oxide resistor.
 4. A parallel RC circuitequalizer as in claim 1, further including: a glass cover above saidsubstrate; and a pair of flexible terminations on either lateral side ofsaid substrate, and respectively connected with said first and secondterminal layers so that said equalizer is surface mountable; whereinsaid flexible terminations comprise flexible polymer material thatencases end portions of said capacitor; one of said flexibleterminations couples said first terminal layer connected to said firstelectrode layer of said capacitor with said at least one connectionterminal associated with said resistor; and the other of said flexibleterminations couples with said second terminal layer connected to saidsecond electrode layer of said capacitor.
 5. A parallel RC circuitequalizer as in claim 1, further including: a cover above saidsubstrate; and a pair of terminations on either lateral side of saidsubstrate, and respectively connected with said first and secondterminal layers, whereby said equalizer is surface mountable by directmounting of said terminations on a supporting surface.
 6. A parallel RCcircuit equalizer as in claim 5, wherein said cover comprises a glasscover.
 7. A parallel RC circuit equalizer as in claim 5, wherein saidequalizer has an impedance of about 50Ω between said pair ofterminations on either lateral side of said substrate.
 8. A parallel RCcircuit equalizer as in claim 5, wherein said terminations compriseflexible terminations.
 9. A parallel RC circuit equalizer as in claim 8,wherein said flexible terminations comprise flexible polymer materialthat encases end portions of said capacitor.
 10. A parallel RC circuitequalizer as in claim 9, wherein one of said flexible terminationscouples said first terminal layer connected to said first electrodelayer of said capacitor with said at least one connection terminalassociated with said resistor.
 11. A parallel RC circuit equalizer as inclaim 9, wherein one of said flexible terminations couples with saidsecond terminal layer connected to said second electrode layer of saidcapacitor.
 12. A parallel RC circuit equalizer having relativelyincreased resonance frequency and useful frequency range, comprising: amonolithic substrate having at least a top surface and at least one pairof opposing lateral edges along said top surface of said substrate, saidsubstrate being elongated along said opposing lateral edges thereof andhaving respective opposite end edges; a capacitor mounted on said topsurface of said substrate; a resistor supported on said substrate topsurface and connected in parallel with said capacitor; a pair ofrespective waveguide elements connected with said capacitor and saidresistor, and supported on said top surface of said substrate so as toextend respectively to said respective opposite end edges of saidsubstrate; and a pair of ground electrodes positioned on said topsurface of said substrate and respectively extending along at least aportion of said opposing lateral edges of said top surface of saidsubstrate; wherein such arrangement of said elements and said electrodesresults in reduced equivalent series inductance of said capacitor, whichrelatively increases the resonance frequency and useful frequency rangeof the resistor and capacitor combined circuit.
 13. A parallel RCcircuit equalizer as in claim 12, wherein: said capacitor comprises asilicon oxynitride (SiON) capacitor; and said resistor comprises atantalum nitride (TaN) resistor.
 14. A parallel RC circuit equalizer asin claim 12, wherein: said capacitor comprises a tantalum capacitor; andsaid resistor comprises a ruthenium oxide resistor.
 15. A parallel RCcircuit equalizer as in claim 12, further including: a cover above saidsubstrate; and a pair of end terminations on either end of saidsubstrate, and respectively connected with said pair of respectivewaveguide elements, whereby said equalizer is surface mountable bydirect mounting of said terminations on a supporting surface.
 16. Aparallel RC circuit equalizer as in claim 15, wherein said equalizer hasan impedance of about 50Ω between said pair of end terminations.
 17. Aparallel RC circuit equalizer as in claim 15, further including a groundtermination centrally received about at least a portion of saidsubstrate and connecting with said pair of ground electrodes.
 18. Aparallel RC circuit equalizer as in claim 17, wherein: said covercomprises a glass cover; and said pair of end terminations and saidground termination comprise flexible terminations.
 19. A parallel RCcircuit equalizer as in claim 18, wherein said flexible terminationscomprise flexible polymer material.
 20. Methodology for relativelyincreasing the resonance frequency and useful frequency range of aparallel RC circuit equalizer, comprising: providing a monolithicsubstrate having at least a top surface and at least one pair ofopposing lateral edges along said top surface of said substrate, saidsubstrate being elongated along said opposing lateral edges thereof andhaving respective opposite end edges; supporting a capacitor on said topsurface of said substrate; supporting a resistor on said substrate topsurface and connected in parallel with said capacitor so as to form anRC circuit therewith; and providing termination material positioned onsaid top surface of said substrate and along at least a portion of eachof said opposing lateral edges thereof, resulting in reduced equivalentseries inductance of said capacitor, which relatively increases theresonance frequency and useful frequency range of the resistor andcapacitor combined circuit.
 21. Methodology as in claim 20, furtherincluding providing at least a pair of coplanar waveguide elementssupported on said substrate and aligned lengthwise along a center lineof said substrate, with said waveguide elements received in series andon either side of said RC circuit and extending from said RC circuit tothe respective opposite end edges of said substrate.
 22. Methodology asin claim 21, wherein said providing termination material includesproviding a pair of ground electrodes positioned respectively along saidlateral edges of said substrate.
 23. Methodology as in claim 22, furtherincluding: providing a cover above said substrate; and providing a pairof flexible terminations received at respective opposite end edges ofsaid substrate, and respectively connected with said waveguide elementsat such opposite end edges.
 24. Methodology as in claim 23, wherein:said flexible terminations comprise flexible polymer material; saidcapacitor comprises one of a silicon oxynitride (SiON) capacitor and atantalum capacitor; and said resistor comprises one of a tantalumnitride (TaN) resistor and a ruthenium oxide resistor.
 25. Methodologyas in claim 23, further including providing a ground terminal receivedat least partly around said substrate and connected with said pair ofground electrodes.
 26. Methodology as in claim 25, further includingsurface mounting said equalizer on a supporting surface.
 27. Methodologyas in claim 20, wherein: said capacitor has a first electrode layer anda second electrode layer, with both of said electrode layers mounted onsaid top surface of said substrate, and separated by a dielectric; andsaid termination material includes a first terminal layer connected tosaid first electrode layer and positioned on said top surface of saidsubstrate and along at least a portion of one of said lateral edgesthereof, and a second terminal layer connected to said second electrodelayer and positioned on said top surface of said substrate and along atleast a portion of said lateral edge thereof opposite to said firstterminal layer.
 28. Methodology as in claim 27, further including: aglass cover above said substrate; and a pair of flexible terminations oneither lateral side of said substrate, and respectively connected withsaid first and second terminal layers so that said equalizer is surfacemountable; and wherein said flexible terminations comprise flexiblepolymer material that encases end portions of said capacitor; one ofsaid flexible terminations couples said first terminal layer connectedto said first electrode layer of said capacitor with said at least oneconnection terminal associated with said resistor; and the other of saidflexible terminations couples with said second terminal layer connectedto said second electrode layer of said capacitor.
 29. Methodology as inclaim 27, further including: providing at least one connection terminalassociated with said resistor; and providing a cover above saidsubstrate, and a pair of terminations on either lateral side of saidsubstrate, and respectively connected with said first and secondterminal layers.
 30. Methodology as in claim 29, further includingsurface mounting said equalizer on a supporting surface.
 31. Methodologyas in claim 29, wherein: said capacitor comprises one of a siliconoxynitride (SiON) capacitor and a tantalum capacitor; and said resistorcomprises one of a tantalum nitride (TaN) resistor and a ruthenium oxideresistor.